Dispensing apparatus

ABSTRACT

A dispensing apparatus to dispense at least one of a first substance and a second substance therefrom includes a head having a first inlet to receive the first substance therethrough, a second inlet to receive the second substance therethrough, and an outlet to expel a mixture of the first substance and the second substance therefrom, with the head configured to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance. The dispensing apparatus further includes a first airless chamber to contain the first substance therein, with the first airless chamber fluidly coupled to the first inlet of the head.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit, under 35 U.S.C. §119, of U.S. Provisional Application Ser. No. 61/506,533, filed on Jul. 11, 2011, and entitled “Airless Dual Chamber Tooth Care Product with Variable Dispensing Pump Head that allows for Variable Blending of the Products from the Dual Chamber. This is a refillable, ecofriendly product.” The disclosure of this U.S. Provisional Application is incorporated herein by reference in its entirety.

BACKGROUND OF DISCLOSURE

1. Field of the Disclosure

Embodiments disclosed herein generally relate to methods and apparatuses to dispense a mixture of a first substance and a second substance. More specifically, embodiments disclosed herein relate to an apparatus that is used to dispense a mixture of a first substance and a second substance therefrom using a first airless chamber and a second airless chamber.

2. Background Art

Dispensing devices and containers are useful in a variety of consumer products, including epoxy adhesives, skin and hair treatment products, and toothpastes. Ordinarily, toothpaste is packaged in flexible tubes with the toothpaste dispensed by squeezing the flexible tube. Then, for many years, Mentadent® employed a multi-cavity dispensing device to dispense toothpaste therefrom. Baking soda was stored in one cavity and hydrogen peroxide was stored in another cavity, in which the ingredients would be dispensed together for use as toothpaste. The ingredients were separately stored from each other to prevent the ingredients from reacting with each other and decomposing in the container when stored.

The basic concept for the Mentadent® product type packaging, which is disclosed in U.S. Pat. No. 4,687,663 (Schaeffer), includes a rigid pump-type dual-cavity dispenser having two closely positioned but separate outlets. A respective dual material stream of peroxide and baking soda is extruded from these outlets. However, when the components of the dual material stream have different densities or rheologies, the device may improperly proportion the quantities of the two materials dispensed from the device. Further, as these materials are dispensed from the device, the quantities of the materials are set and may not be varied.

Accordingly, there exists a need that may address these concerns, such as to more adeptly accommodate the varying ingredients, such as different toothpaste ingredients and substances, which may be used within a dispensing device.

SUMMARY OF CLAIMED SUBJECT MATTER

In one aspect, embodiments disclosed herein relate to a dispensing apparatus to dispense at least one of a first substance and a second substance therefrom. The dispensing apparatus includes a head having a first inlet to receive the first substance therethrough, a second inlet to receive the second substance therethrough, and an outlet to expel a mixture of the first substance and the second substance therefrom, with the head configured to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance. The dispensing apparatus further includes a first airless chamber to contain the first substance therein, with the first airless chamber fluidly coupled to the first inlet of the head.

In another aspect, embodiments disclosed herein relate to a method to manufacture a dispensing apparatus that dispenses to dispense at least one of a first substance and a second substance therefrom. The method includes fluidly coupling a first airless chamber to a first inlet of a head, the heading having the first inlet to receive the first substance therethrough from the first airless chamber and having a second inlet to receive a second substance therethrough. The head also has an outlet to expel a mixture of the first substance and the second substance therefrom, with the head configured to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance.

In yet another aspect, embodiments disclosed herein relate to a dispensing apparatus to dispense toothpaste for oral care therefrom having at least one of a first substance and a second substance therefrom. The dispensing apparatus includes a head having a first inlet to receive the first substance therethrough, a second inlet to receive the second substance therethrough, an outlet to expel a mixture of the first substance and the second substance therefrom, and an adjustment mechanism to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance. The dispensing apparatus further includes a first airless cartridge to contain the first substance therein, with the first airless cartridge fluidly coupled to the first inlet of the head, and a second airless cartridge to contain the second substance therein, with the second airless cartridge fluidly coupled to the second inlet of the head.

Other aspects and advantages of the invention will be apparent from the following description and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B show perspective views of a dispensing apparatus in accordance with one or more embodiments disclosed herein.

FIGS. 2A, 2B, and 2C show multiple views of a head of a dispensing apparatus in accordance with one or more embodiments disclosed herein.

DETAILED DESCRIPTION

Specific embodiments of the present disclosure will now be described in detail with reference to the accompanying Figures. Like elements in the various figures may be denoted by like reference numerals for consistency. Further, in the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the embodiments disclosed herein may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

Furthermore, those having ordinary skill in the art will appreciate that when describing connecting a first element to a second element, it is understood that connecting may be either directly connecting the first element to the second element, or indirectly connecting the first element to the second element. For example, a first element may be directly connected to a second element, such as by having the first element and the second element in direct contact with each other, or a first element may be indirectly connected to a second element, such as by having a third element, and/or additional elements, connected between the first and second elements.

In one aspect, embodiments disclosed herein relate to a dispensing apparatus to dispense a mixture of a first substance and a second substance therefrom. The apparatus includes a head having a first inlet, a second inlet, and an outlet, in which the first substance is received through the first inlet, the second substance is received through the second inlet, and the outlet is used to expel the mixture of the first substance and the second substance therefrom. Further, the head is used to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance, as desired. The apparatus may further include a first airless chamber to contain the first substance therein, with the first airless chamber fluidly coupled to the first inlet of the head, and may also include a second airless chamber to contain the second substance therein, with the second airless chamber fluidly coupled to the second inlet of the head.

The first airless chamber may include or be formed as a first cartridge having a first piston removably received therein, and similarly the second airless chamber may include or be formed as a second cartridge having a second piston removably received therein. This may enable the first substance and the second substance contained within the first cartridge and the second cartridge, respectively, to be replaced or refilled, as desired. Further, the apparatus may include an outer housing such that the head is connected to the outer housing with the first cartridge and the second cartridge removably received within the outer housing, such as by having an end cap removably secured to the outer housing. As such, this may enable the first cartridge and the second cartridge to be replaced or refilled, as desired.

Further, the dispensing apparatus may be used to dispense toothpaste for oral care, such as by having the mixture of the first substance and the second substance used as toothpaste. For example, the first substance may include a teeth cleaning solution, which may be used for cleaning and polishing teeth, and the second substance may include a peroxide solution, which may be used for whitening or oxygenating teeth. One of the first substance and the second substance may include aloe vera as well, such as by including aloe vera within the teeth cleaning solution. Furthermore, the ratio of the mixture may be varied, as desired, such as by including an adjustment mechanism within the head to vary the ratio of the mixture between the first substance and the second substance, as desired. For example, the adjustment mechanism may be set such that the mixture expelled from the head is a desired ratio of the first substance and the second substance, and/or the adjustment mechanism may be set such that the mixture expelled from the head is substantially all of the first substance or substantially all of the second substance.

Referring now to FIGS. 1A and 1B, multiple perspective views of an apparatus 101 to dispense a first substance and/or a second substance therefrom in accordance with one or more embodiments disclosed herein are shown. FIG. 1A shows a perspective view of the apparatus 101 assembled, and FIG. 1B shows a perspective view of the apparatus 101 partially disassembled.

As shown, the apparatus 101 may include an outer housing 103, in which the outer housing 103 may include a first end 105 and a second end 107. As such, the apparatus 101 includes a head 151 that may be connected to the outer housing 103, such as connected to the first end 105 of the outer housing 103. Further, as shown, a cap 153 may be connected to the head 151 such as to substantially cover the head 151. In FIG. 1A, the cap 153 is shown as connected to the head 151, whereas in FIG. 1B, the cap 153 is shown as removed from the head 151. The head 151 may be connected to the outer housing 103 using an interference fit (e.g., snap fit) type connection, as depicted. Similarly, the cap 153 may be connected to the head 151 using an interference fit type connection. However, those having ordinary skill in the art will appreciate that the head and the cap may be connected within the apparatus using any type of connector or method known in the art.

The apparatus 101 may further include a first airless chamber 111A and a second airless chamber 111B, in which the first airless chamber 111A contains the first substance to be dispensed from the apparatus 101 therein and the second airless chamber 111B contains the second substance to be dispensed from the apparatus 101 therein. As used herein, an airless chamber refers to a chamber that may be used to contain and dispense a substance therefrom without also introducing or allowing any substantial amount of air, or any gas for that matter, into the chamber. As such, a substance that may be adversely affected by air, such as a substance that may deteriorate or become less effective from the presence of air (e.g., a peroxide substance), may be contained within the airless chamber to avoid such adverse effects. Those having ordinary skill in the art, however, will appreciate that the present disclosure is not so limited, as the present disclosure contemplates embodiments having one or more non airless chambers as well. In such embodiments, those substances that may not be adversely affected by air may then be contained within non airless chambers.

As discussed above, the apparatus 101 may be used to dispense a mixture of the first substance and the second substance therefrom. As such, the head 151 of the apparatus 101 may include, at least, a first inlet, a second inlet, and an outlet (discussed and shown in more detail below with respect to FIGS. 2A, 2B, and 2C). The first airless chamber 111A may be fluidly coupled to the first inlet of the head 151 such that the first substance contained within the first airless chamber 111A may be received into the first inlet of the head 151. Similarly, the second airless chamber 111B may be fluidly coupled to the second inlet of the head 151 such that the second substance contained within the second airless chamber 111B may be received into the second inlet of the head 151.

Further, the outlet of the head 151 may then be used to expel a mixture of the first substance and the second substance therefrom. As such, the head 151 may be used to vary a ratio of the mixture dispensed from the apparatus 101, as desired, such as by varying the ratio of the mixture from substantially all of the first substance to substantially all of the second substance, and any other ratio of the mixture included therebetween (e.g., ratios of the first substance to the second substance may include 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, and 90:10).

One having ordinary skill in the art will appreciate that the first airless chamber 111A and/or the second airless chamber 111B may include or be formed as a cartridge. As such, the first airless chamber 111A is formed as a first cartridge having a first end 113A and a second end 115A with a piston 117A removably received therein, and the second airless chamber 111B is formed as a second cartridge having a first end 113B and a second end 115B with a piston 117B removably received therein. The use of one or more cartridges within the present disclosure may prevent the use of additional valves and/or diptubes within the dispensing apparatus, thereby reducing the complication and arrangement of the dispensing apparatus.

In accordance with one or more embodiments disclosed herein, as the first substance is dispensed from the apparatus 101, the first substance may expel through an outlet formed at the first end 113A of the first cartridge, in which the piston 117A may then move from the second end 115A towards the first end 113A of the first cartridge as the first substance is expelled therefrom. Similarly, the second substance may expel through an outlet formed at the first end 113B of the second cartridge, in which the piston 117B may then move from the second end 115B towards the first end 113B of the second cartridge as the second substance is expelled therefrom.

Further, as the piston 117A is removably received within the first cartridge, the piston 117A may be removed and reinserted into the first cartridge to refill or replace the first substance within the first cartridge, as desired is necessary or desired. Similarly, as the piston 117B is removably received within the second cartridge, the piston 117B may be removed and reinserted into the second cartridge to refill or replace the second substance within the second cartridge, as is necessary or desired.

Accordingly, as shown in FIGS. 1A and 1B, the apparatus 101 may have the first airless chamber 111A and/or the second airless chamber 111B removably received within the outer housing 103. For example, the outer housing 103 may have an end cap 109 removably secured thereto, such as by having the end cap 109 threadedly connected to the second end 107 of the outer housing 103. As such, the first airless chamber 111A and the second airless chamber 111B, which may be cartridges as shown, may be removably received within the outer housing 103 of the apparatus 101 through the second end 107, thereby enabling the first airless chamber 111A and/or the second airless chamber 111B to be refilled or replaced within the apparatus 101, as is necessary or desired.

Referring now to FIGS. 2A, 2B, and 2C, multiple views of a head 251 to vary and dispense therefrom a ratio of a mixture of a first substance and a second substance in accordance with one or more embodiments disclosed herein are shown. FIG. 2A shows a cross-sectional view of the head 251 when assembled, whereas FIGS. 2B and 2C show perspective exploded views of the head 251 with parts of the head 251 disassembled.

As shown in FIGS. 2A, 2B, and 2C, the head 251 may include, a first inlet 255A, a second inlet 255B, and an outlet 257, at least. As discussed above, the first inlet 255A may be fluidly coupled to a first airless chamber such that the first substance contained within the first airless chamber may be received into the first inlet 255A of the head 251, and the second inlet 255B may be fluidly coupled to a second airless chamber such that the second substance contained within the second airless chamber may be received into the second inlet 255B of the head 251. The first substance and the second substance received within the first inlet 255A and the second inlet 255B, respectively, may be drawn into the head 251 to follow a flowpath, shown by directional arrow A. The first substance and the second substance may follow the flowpath A to then be expelled and dispensed from the outlet 257 formed in the head 251. The head 251 may include more than one outlet 257, as shown in FIG. 2A particularly, but in an embodiment with one outlet 257, the first substance and the second substance may be mixed internally within the head 251 to be dispensed as a mixture from the outlet 257 of the head 251. As such, in one or more embodiments, the dispensing apparatus of the present disclosure may include a mixing member or mechanism, such as within the flow path of the head, in which the mixing member may be used to mix and/or stir the first substance with the second substance before being dispensed from the dispensing apparatus. Further, the first substance and the second substance may be mixed internally within the head closest to the outlet of the head, such as having the first substance and the second substance mix adjacent the outlet of the head before being dispensed and expelled through the outlet of the head. This may prevent any adverse affects to the first substance and the second substance that may occur from having the first substance and second substance mix and interact within the head before being dispensed, such as having one of the first substance and the second substance spoil if in contact with the other for a prolonged period of time. Accordingly, those having ordinary skill in the art will appreciate that the present disclosure encompasses all of these embodiments.

In accordance with one or more embodiments disclosed herein, the head 251 of the dispensing apparatus of the present disclosure may be formed from multiple parts, components, and elements that may be assembled together. As such, the head 251 may include a housing 261 and a base 265 connected to each other, in which a cap 253 may be removably received over the housing 261 of the head 251. Further, the first inlet 255A and the second inlet 255B, as shown, may be formed or included within the base 265, and the outlet 257 may be formed or included within the housing 261. As the housing 261 and the base 265 of the head 251 are connected together, multiple parts, components, and elements may be assembled together and disposed between the housing 261 and the base 265 within the head 251.

For example, as shown, the base 265 may have a first chamber 267A formed therein corresponding to the first inlet 255A and may have a second chamber 267B formed therein corresponding to the second inlet 255B. A cylindrical unit 269 may then be included within the head 251 such that a first cylinder 271A of the cylindrical unit 269 may be received within the first chamber 267A of the base 265 and a second cylinder 271B of the cylindrical unit 269 may be received within the second chamber 267B of the base 265. A first valve 273A may be disposed between the first cylinder 271A and the base 265 adjacent the first inlet 255A, and a second valve 273B may be disposed between the second cylinder 271B and the base 265 adjacent the second inlet 255B.

Further, a first piston 275A may be received within the first cylinder 271A of the cylindrical unit 269 with a first spring 279A disposed therebetween, and a second piston 275B may be received within the second cylinder 271B of the cylindrical unit 269 with a second spring 279B disposed therebetween. Accordingly, as the first piston 275A moves upward and downward within the first cylinder 271A, compressing the first spring 279A, the first substance is received through the first inlet 255A and is expelled and dispensed through the outlet 257 of the housing 261. Similarly, as the second piston 275B moves upward and downward within the second cylinder 271B, compressing the second spring 279B, the second substance is received through the second inlet 255B and is expelled and dispensed through the outlet 257 of the housing 261.

The head 251 may also include an adjustment mechanism 281, in which the adjustment mechanism may be used to vary the ratio of the mixture between the first substance and the second substance dispensed from dispensing apparatus. As shown in FIG. 2A, in particular, the adjustment mechanism 281 may be disposed within the housing 261 of the head 251 and may be rotatable about an axis 291 of the head 251 with respect to the first piston 275A and the second piston 275B. As such, the adjustment mechanism 281 may be rotatable to selectively engage the first piston 275A and/or the second piston 275B, as desired.

For example, the adjustment mechanism 281 may include a handle 283, in which the handle 283 of the adjustment mechanism 281 may be engaged, such as by a user, to have the adjustment mechanism 281 rotate about pivot point 285 and engage an upper plate portion 277A of the first piston 275A and/or engage an upper plate portion 277B of the first piston 275B. Based upon the relative rotational position of the adjustment mechanism 281 with respect to the first piston 275A and the second piston 275B, the adjustment mechanism 281 may selectively engage the upper plate portion 277A of the first piston 275A, thereby moving the first piston 275A to receive the first substance within the head 251 through the first inlet 255A, and/or may selectively engage the upper plate portion 277B of the second piston 275B, thereby moving the second piston 275B to receive the second substance within the head 251 through the second inlet 255B.

As such, the ratio of the mixture between the first substance and the second substance expelled and dispensed through the outlet 257 of the head 251 may be controlled based upon the relative movement of the first piston 275A with respect to the second piston 275B when engaged by the adjustment mechanism 281. As shown in FIG. 2A, the adjustment mechanism 281 is shown only engaging and moving the first piston 275A, and therefore only the first substance is received through the first inlet 255A and expelled through the outlet 257. However, as the adjustment mechanism 281 is rotated about the axis 291, the adjustment mechanism 281 may engage and move both the first piston 275A and the second piston 275B in a desired ratio or proportion with respect to each other, thereby controlling the ratio of the mixture between the first substance and the second substance expelled and dispensed through the outlet 257 of the head 251. Accordingly, the adjustment mechanism 281 may be set such that the mixture expelled from the head 251 is a desired ratio of the first substance and the second substance, and/or the adjustment mechanism 281 may be set such that the mixture expelled from the head 251 is substantially all of the first substance or substantially all of the second substance. Further, an example of such a head that may be used herein is disclosed in U.S. Pat. No. 7,240,808, which is hereby incorporated by reference in its entirety.

As discussed above, a dispensing apparatus in accordance with the present disclosure may be used to dispense toothpaste for oral care, such as by having the mixture of the first substance and the second substance used as toothpaste. For example, the first substance may include a teeth cleaning solution, which may be used for cleaning and polishing teeth, and the second substance may include a peroxide solution, which may be used for whitening or oxygenating teeth. One of the first substance and the second substance may include aloe vera as well, such as by including aloe vera within the teeth cleaning solution. As such, if one desired to only clean and polish teeth, the user may adjust the adjustment mechanism of the head of the dispensing apparatus to only dispense the teeth cleaning solution, or if one desired to only whiten and oxygenate teeth, the user may adjust the adjustment mechanism of the head of the dispensing apparatus to only dispense the peroxide solution. Further, based upon the desired results, the adjustment mechanism may be adjusted to have the dispensing apparatus dispense any ratio of the teeth cleaning solution and the peroxide solution with respect to each other. The mixture expelled from the head of the dispensing apparatus may then be directly applied from the outlet of the head to a toothbrush for convenient use.

As shown and discussed above, the dispensing apparatus of the present disclosure has been shown to have two airless chambers. However, those having ordinary skill in the art will appreciate that embodiments disclosed herein are not so limited, as the present disclosure contemplates one or more embodiments using only a single airless chamber, or using more than two airless chambers. Further, the dispensing apparatus of the present disclosure has been shown to have cartridges for the airless chambers. However, those having ordinary skill in the art will appreciate that embodiments disclosed herein are not so limited, as the present disclosure contemplates using other types of airless chambers, such as a flexible bag and the like.

An apparatus in accordance with one or more embodiments of the present disclosure may be useful in multiple areas, such as within oral care. For example, the apparatus may allow for variable blending and dispensing of substances included within the chambers, as is desired or necessary at varying percentages or ratios. Further, the apparatus may allow for the dispensing substances to be refilled or replaced as desired, such as by replacing the airless chambers or the substances included therein, thereby increasing the utility of the apparatus and reducing waste. As such, the apparatus of the present disclosure may be environmentally friendly, as this may benefit in recycling containers for reuse and/or recycling the apparatus altogether for reuse, as is necessary or desired.

While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the disclosure should be limited only by the attached claims. 

1. A dispensing apparatus to dispense at least one of a first substance and a second substance therefrom, the apparatus comprising: a head having a first inlet to receive the first substance therethrough, a second inlet to receive the second substance therethrough, and an outlet to expel a mixture of the first substance and the second substance therefrom, the head configured to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance; and a first airless chamber to contain the first substance therein, the first airless chamber fluidly coupled to the first inlet of the head.
 2. The dispensing apparatus of claim 1, wherein the first airless chamber comprises a first cartridge having a first piston removably received therein.
 3. The dispensing apparatus of claim 1, further comprising: a second airless chamber to contain the second substance therein, the second airless chamber fluidly coupled to the second inlet of the head.
 4. The dispensing apparatus of claim 3, further comprising: an outer housing having the head connected to the outer housing with the first cartridge and the second cartridge removably received within the outer housing.
 5. The dispensing apparatus of claim 4, wherein an end cap is removably secured to the outer housing such that the first cartridge and the second cartridge are removably received within the outer housing.
 6. The dispensing apparatus of claim 1, wherein the mixture of the first substance and the second substance comprises toothpaste for oral care.
 7. The dispensing apparatus of claim 6, wherein at least one of the first substance and the second substance comprises aloe vera.
 8. The dispensing apparatus of claim 6, wherein at least one of the first substance and the second substance comprises a peroxide solution.
 9. The dispensing apparatus of claim 1, wherein the head comprises an adjustment mechanism to vary the ratio of the mixture between substantially all of the first substance and substantially all of the second substance.
 10. A method to manufacture a dispensing apparatus that dispenses to dispense at least one of a first substance and a second substance therefrom, the method comprising: fluidly coupling a first airless chamber to a first inlet of a head, the heading having the first inlet to receive the first substance therethrough from the first airless chamber and having a second inlet to receive a second substance therethrough; and the head having an outlet to expel a mixture of the first substance and the second substance therefrom, the head configured to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance.
 11. The method of claim 10, wherein the first airless chamber comprises a first cartridge having a first piston removably received therein.
 12. The method of claim 10, further comprising: fluidly coupling a second airless chamber to the second inlet of the head, the second inlet to receive the second substance therethrough from the second airless chamber.
 13. The method of claim 12, further comprising: connecting the head to an outer housing with the first cartridge and the second cartridge removably received within the outer housing.
 14. The method of claim 13, further comprising: removably securing an end cap to the outer housing such that the first cartridge and the second cartridge are removably received within the outer housing.
 15. The method of claim 10, wherein the mixture of the first substance and the second substance comprises toothpaste for oral care.
 16. The method of claim 10, wherein the head comprises an adjustment mechanism to vary the ratio of the mixture between substantially all of the first substance and substantially all of the second substance.
 17. A dispensing apparatus to dispense toothpaste for oral care therefrom having at least one of a first substance and a second substance therefrom, the apparatus comprising: a head having a first inlet to receive the first substance therethrough, a second inlet to receive the second substance therethrough, an outlet to expel a mixture of the first substance and the second substance therefrom, and an adjustment mechanism to vary a ratio of the mixture between substantially all of the first substance and substantially all of the second substance; a first airless cartridge to contain the first substance therein, the first airless cartridge fluidly coupled to the first inlet of the head; and a second airless cartridge to contain the second substance therein, the second airless cartridge fluidly coupled to the second inlet of the head.
 18. The dispensing apparatus of claim 17, further comprising: an outer housing having the head connected to the outer housing with the first cartridge and the second cartridge removably received within the outer housing.
 19. The dispensing apparatus of claim 18, wherein an end cap is removably secured to the outer housing such that the first cartridge and the second cartridge are removably received within the outer housing.
 20. The dispensing apparatus of claim 17, wherein the first airless cartridge has a first piston removably received therein and the second airless cartridge has a second piston removably received therein. 